Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd82accf0116e660…

MALICIOUS

PDF

46.1 KB Created: 2020-08-31 09:07:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: edb07d2eddd6d2d5206611adf6d16295 SHA-1: 75c49de338a177a5dcf8f08841102bbdd59f4fe1 SHA-256: fd82accf0116e6604885679ed700218962afca1f3862a89399d1d32d52eec3c1
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by multiple critical heuristics for containing malicious redirector links and a link farm. The document body, though heavily obfuscated, contains a URL that matches the redirector link found in the heuristics. The primary malicious indicator is the presence of a link to `ttraff.ru`, which is known malicious infrastructure. The document also contains numerous links to `static.usrfiles.com`, which appear to be part of a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/wix?keyword=tecnologia+3+eso+ejercicios+resuelto
    • https://static.usrfiles.com/ugd/b8c837_ef21abd4d10d4d0490ede476d398db3f.pdf
    • https://static.usrfiles.com/ugd/81d6a4_81b20bfb10414471a2642fcdbcf8f5f1.pdf
    • https://static.usrfiles.com/ugd/d775a9_d195911cd8344c0abe7aa95b48d4ab9f.pdf
    • https://static.usrfiles.com/ugd/9e53d4_b262d42731534ef7997845263ac69954.pdf
    • https://static.usrfiles.com/ugd/2f7815_5b0c7fd7422543ceabd39cb9da956791.pdf
    • https://static.usrfiles.com/ugd/f80014_198a1b1695e04a9eb34938c0900a462b.pdf
    • https://static.usrfiles.com/ugd/b8c837_1008a45593a0482ba727a4884fcec52b.pdf
    • https://static.usrfiles.com/ugd/b8c837_e78df294ef654ab2b940ce7421fba450.pdf
    • https://static.usrfiles.com/ugd/724fb5_00406bf851a540059305a9520a0c541e.pdf
    • https://static.usrfiles.com/ugd/8a419d_d167ad1aaf5142ec858128d8ed151072.pdf
    • https://static.usrfiles.com/ugd/b8c837_c970f4ca78c74065a324323e999182f0.pdf
    • https://static.usrfiles.com/ugd/217d68_984a9ddfbf954b349eac69baf6d04997.pdf
    • https://static.usrfiles.com/ugd/b8c837_a69c188e6dac4e05bb7d09d2ebeec3c7.pdf
    • https://static.usrfiles.com/ugd/d54300_2e2c9dce076249e1b1d6bcf0159b4339.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000064a0.bin
503ffffc5c0c101c77f8fc2bdbfbbc4efaa8d817bb0e9c8393cbb46e08223249
pdf-font-stream PDF embedded font (sfnt) at offset 0x64A0 5036 bytes
font_01_sfnt_off000075cb.bin
fe72ae0dbb23994ca5a197553881dbce3815903fd462a9cffedaf6b94ed509b4
pdf-font-stream PDF embedded font (sfnt) at offset 0x75CB 11540 bytes
font_02_sfnt_off00009b64.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x9B64 4324 bytes